Federal Express (NYSE:FDX) reported decent earnings for its fiscal fourth quarter on Tuesday, but it delivered cautious guidance going forward, which should concern investors on a macro basis. The good news was that net income was up 14%, net of extraordinary charges, beating analysts estimates. This was driven by very healthy growth in daily ground package volume, which rose 3% and contributed to a 9% revenue increase.

But this is Federal Express, and the express part of the business saw average daily package volume fall 5%, generating only a 3% revenue gain. Overall sales across the company rose 4%. So that wasn’t so hot, but a 14% overall income increase would make anybody happy.

Right? Well, that would be true except that FedEx is projecting a disappointing fiscal first quarter.

So what’s going on?

The problem stems from my overall concern about real unemployment being 15% in the U.S., combined with global deleveraging. Economic growth of the past decade was driven by easy credit and extreme levels of leverage. Now, the world is getting out from under that debt — everybody is paying off loans instead of spending money.

That slows the world’s business, which means fewer things get shipped. FedEx is now forecasting 2.4% global GDP growth vs. 2.9% at the start of 2012. However, in the conference call, company executives said, “It’s important to point out that successful management of the debt crisis in Europe and the avoidance of significant tax increases next year in the U.S. are important assumptions in our forecast.”

I think we’re safe on the latter, but not on the former. On top of this, FedEx will have to deal with higher pension expenses and higher depreciation costs.

The silver lining is that FedEx will increase prices, which it can do because it’s one of the biggest players in the industry along with United Parcel Service (NYSE:UPS). Choices are limited, so people will pay up. FedEx has a fantastic balance sheet with $2.8 billion in cash and only $1.7 billion in debt. Pretty amazing, considering it has so many costs, what with airplanes and trucks.

With $3 net cash per share, and FY12 earnings of $7.35 expected, FedEx trades at about 13x earnings. I’d say that despite a global slowdown, FedEx is certainly here to say, and may even be fairly valued. I wouldn’t be scared of getting in .